1.3.4 Web Technologies

Question 1

What does HTML stand for?

Answer 1

• Hyper Text Markup Language

Question 2

What is HTML and what can it do?

Answer 2

• Set of instructions telling how images and text should be displayed in a web browser.
• Webpages coded with HTML are read by web browsers which then interpret the tags and render the page visually.

Question 3

What is the html tag

Answer 3

• Tells the browser that the file has been created using html. It begins with this tag and ends with this tag.

Question 4

What is the head

tag?

Answer 4

• Contains the webpages header information.
• It is a container for metadata (data about data) and placed between and tags.

Question 5

What is the title

tag?

Answer 5

• Defines the title of the document. Shown in the title bar.
• It is a required tag for all HTML documents.

Question 6

What is the body tag?

Answer 6

• Contains the webpage’s content
• Defines the document’s main text, headings, paragraphs, images, hyperlinks, tables, lists.

Question 7

What is the h* tag

Answer 7

• Define headings in order of importance. The h1 tag is the most important

Question 8

What is the image tag?

Answer 8

• Used to embed an image into the HTML document. Images are linked to webpages.

Question 9

img src = “Dog.jpg alt = ”picture of dog”

What does the tags src and alt mean?

Answer 9

• Src: Specifies the file path of the image
• Alt : Specifies the alternate text for the image if it can’t be displayed.

Question 10

What is the a tag?

Answer 10

• Defines a hyperlink which is used to link 1 page to another .
• The most important attribute of the a tag is href, which indicates the link’s destination

Question 11

What are the colours for a link that was unvisited, visited and active?

Answer 11

• Unvisited link - Blue underlined
• Visited link - Purple Underlined
• Active Link - Red Underlined

Question 12

What is the ol tag?

Answer 12

• Defines an ordered list. Can be numerical or alphabetical.

Question 13

What is the li tag?

Answer 13

• Used to define each item in a list.

Question 14

What is the ul tag?

Answer 14

• Defines an unordered (bulleted list)

Question 15

What does CSS stand for and what does it do?

Answer 15

• Cascading style sheets
• Describes how HTML elements are to be displayed on screens, paper, other media
• Saves a lot of work by allocating developers to control the layout of multiple pages at once.

Question 16

What are the different ways CSS can be used?

Answer 16

• Can be included directly inside the HTML file if it is defined inside a style tag. - it only affects the style of that page.
• Can use a separate external style sheet and change the look of the entire site by amending that file. Use link tags to link CSS page to HTML page.

Question 17

What are some of the different properties of CSS

Answer 17

• background-color
• border-color
• border-width
• border-style
• font-family
• font-size

Question 18

What is the code that links the external CSS file to the HTML page?

Answer 18

• link rel “stylesheet” href = “style.css” (in tags)

Question 19

What are the different ways of linking parts of the HTML page to the Stylesheet?

Answer 19

• Using div tags
  
  • div class = “main” in HTML page main{ (in stylesheet)
• Using id selector
  
  • ol id = “ordered list” - (HTML page) #ordered list { - in stylesheet {

Question 20

Describe 1 advantage of storing CSS in an external file rather than embedded within HTML files

Answer 20

• Content and formatting and kept separate (1)
• Changes can be made to the external style sheet and affect the whole site (1) saving time (1) and ensuring consistency (1)
• Stylesheets can be changed for different themes, or different devices (1)

Question 21

Describe what is meant by the term Javascript

Answer 21

• A programming language that runs on a web browser(1)
• That can be embedded into HTML(1)
• With script tag (1) to add interactivity to a page(1)

Question 22

What type of tags does the form element have?

Answer 22

• input tags
• textarea tags
• button tags
• select tags
• option tags
• label tags
• output tags

Question 23

What does an action attribute tell the browser

Answer 23

• Tells the browser it needs to send any submitted form data to a page on the server indicated by the tags.

Question 24

How are simple text boxes and buttons defined with?

Answer 24

• With the input tags
• The type attribute determines the type of input
• Inputs are given an id - can refer to this in Javascript.

Question 25

What does a search engine use?

Answer 25

* The search engine runs the request against its index it doesnt actually search every single web page.

Question 26

What is indexing?

Answer 26

* Is the process of a search engine collecting, sorting and storing data in its index * Therefore the index is the place where all the data the search engine has gathered is located.

Question 27

The index must be constantly updated to ensure that?

Answer 27

* New sites/ pages are added * Old sites/pages are removed * Broken links are updated

Question 28

What do spiders/crawlers do in the WWW?

Answer 28

* They travel the world wide web * They index any pages, content, metadata they find and map links between pages by following all: * Internal links * External links * By doing this they continuously add and update the index.

Question 29

Explain what happens when a search engine indexes the page - no ranking?

Answer 29

* A program called a spider/crawler/bot (1) * Traverses the web/ following the links (1) * It takes each word in the document (1) * It adds an entry for the page in the index (1) alongside the word's position on the page (1)

Question 30

What is the Page Rank algorithm?

Answer 30

* Trademarked algorithm used to compile and rank website pages and the lists of results are returned by a search engine. * It checks the number and quality of links to a page to determine how important it is. * Makes an assumption : important websites are linked to/from other websites.

Question 31

What does C(Tn) mean in the page rank algorithm?

Answer 31

* Is the total count of outbound links (links from your site to other sites) from the webpage n, including inbound links (pointing from other websites to your site) to page A

Question 32

What is PR(Tn) / C(Tn) in the page rank algorithm?

Answer 32

* Is the share of the vote page A gets from pages T1 through Tn. These vote fractions are added together and multiplied by d.

Question 33

What is d in the page rank algorithm?

Answer 33

* Damping factor that prevents PR(Tn)/ C(Tn) from having too much influence. Its notionally set to 0.85

Question 34

How does the page rank algorithm work?

Answer 34

* The web page's pagerank is determined in part by the pagerank of other pages linking to it. * Doesnt need to know the page rank of back-linked pages * First, the algorithm makes an informed guess. After iterations it hones into the correct page rank * Once the final page rank is achieved, the average page rank of all pages will be 1.

Question 35

The site's owner notices that the site doesn't come up high in the results from a search engine that uses PageRank algorithm. State what would affect his site's ranking?

Answer 35

* The number of sites that link to their site * The pageRank of the linking sites * The number of outward links from the site

Question 36

What are the names of the 2 types of connected entities used when using the internet?

Answer 36

* The client/user * The server holding the web page or resource we want.

Question 37

What are the simple interaction steps when a user wants to review a web page?

Answer 37

* The client requests the page * The client's request is recieved by the web server * The web server returns the page to the client's browser.

Question 38

What are the features of client side processing?

Answer 38

* Initial data validation (Javascript) * Manipulates user interface elements * Applies website styles CSS * Reduces load on the server * Reduces the amount of web traffic

Question 39

What are the features of server-side processing

Answer 39

* Provides further validation * Queries and updates the server database * Encodes data into readable HTML and responds to queries submitted by HTML forms * Keeps organisation data secure * Performs complex calculations and adds extra functionality to a website

Question 40

Are these client side or server side: 1. Code executes on the local browser 2. Code executes on a remote computer 3. Reduces load on the server 4. Essential for accurate querying of a database 5. Executing Javascript code 6. Initial validation of inputs 7. SQL processes take place

Answer 40

1. Client side 2. Server side 3. Client side 4. Server side 5. Client side 6. Client side 7. Server side

Question 41

Are these client side or server side? 1. Scripts are embedded on the webpage 2. Faster response times 3. Cookies to personalise user's experience 4. Processing overhead that can decrease performance and force the user to wait for the page to be processed and recreated

Answer 41

1. Client side 2. Client side 3. Client side 4. Server side

Question 42

What is the purpose compression?

Answer 42

* Reduce the size of files * Reduce download times * Reduce storage requirements * Makes better use of bandwidth

Question 43

What are the 2 methods of compression?

Answer 43

* Lossy and Lossless * When a compressed file arrives at its destination it needs to be uncompressed to be read

Question 44

What are the features of Lossy Compression?

Answer 44

* Some data is lost when the file is compressed * Reduces quality but significantly reduces file size * Suitable for images, audio and video

Question 45

What are the features of lossless compression?

Answer 45

* None of the original data is lost * Original file can be recreated * Suitable for executable files and documents

Question 46

Describe what is meant by Lossy Compression Explain whether lossy or lossless compression would be most appropriate to store the photograph. Justify your response

Answer 46

a) An algorithm that makes a file storage/ file smaller but accuaracy with what it represents data is reduced/information is lost in the process b) Lossy Compression. Some loss of detail is acceptable. Unlikely to be noticeable. Will make the file size smaller than lossless.

Question 47

Exam Question: Why is Javascript interpreted rather than compiled?

Answer 47

* JavaScript is likely to be run on a variety of machines (1) * with different processors / architectures (1). * Compiled code is machine dependent (1) whereas interpreters run on high level code (1) which is machine independent (1).

Question 48

Describe 1 advantage of storing CSS in an external file

Answer 48

* Content and formatting are kept separate (1). * Changes can be made to the external style sheet and affect the whole site (1) * saving time (1) * and ensuring consistency (1). * Stylesheets can be changed for different themes, or different devices (1).

Question 49

Exam Question: Discuss the differences of using Client side and Server side processing with respect to webpages

Answer 49

* Client side processing doesn’t require data to be sent back and forth meaning code is much more responsive. * Code is visible which means it can be copied. * Server side processing takes away the reliance of the browser having the correct interpreter * . It hides the code from the user, protecting copyright and avoiding it being amended/circumvented. * Server side processing puts extra load on the server. This is at the cost of the company hosting the website.

Question 50

Answer 50